Drylands cover 40% of the earth’s terrestrial surface and are home to over 2 billion people, the majority of whom belong to the poorest people in the world (MA 2005b). Most of the ‘poorest’ people living in drylands are pastoralists, hunter-gatherers and other traditional communities that can be considered as indigenous peoples according to international standards (ILO Convention No.169 Article 1). Dryland ecosystems are characterized by the limited availability of water and consequently a relatively low primary productivity. However, it is as much the uncertainty of precipitation as the total volume that determines many features of dryland ecosystems, as well as the livelihood strategies of the people. Based on the climatic conditions drylands are divided into dry subhumid, semiarid, arid and hyperarid areas.
Drylands host a unique array of biodiversity. About 32% of the global ‘‘biodiversity hotspots’’ are in drylands. At least 30% of the world’s cultivated plants originate in drylands and over 40% of all cultivated lands worldwide are within drylands. According to the Millennium Ecosystem Assessment there is medium certainty that some 10–20% of the drylands are degraded and affecting the livelihoods of millions of people. Desertification thus ranks among the greatest environmental challenges. However, at the same time it is important not to forget that drylands are very resilient ecosystems. Plant and animal species and microorganism have developed numerous coping strategies to survive the high variability of rainfall – very short life cycles to make use of periods of water availability as well as numerous strategies to escape drought (Bonkoungou and Niamir-Fuller 2001). Drylands that look deserted after a period of drought are not necessarily degraded (MA 2005b; Bonkoungou and Niami-Fuller 2001). Similarly, people living in drylands have developed complex pastoral and cropping systems to cope with the erratic and harsh climate (Bonkoungou and Niamir-Fuller 2001).
Scientific studies on the current and projected impact of climate change in drylands are notoriously few. Although climate change will affect different regions in different ways, for drylands in general it is projected that climate change will lead to a decrease in water availability and quality while extreme weather events such as droughts and floods are projected to increase (IPCC 2007a; MA 2005a). In addition, although agricultural productivity is expected to rise in some regions, it will likely decrease overall in drylands (IPCC 2007a; MA 2005a). “Agricultural production, including access to food, in many African countries and regions is projected to be severely compromised by climate variability and change. The area suitable for agriculture, the length of growing seasons and yield potential, particularly along the margins of semi-arid and arid areas, are expected to decrease. This would further adversely affect food security and exacerbate malnutrition in the continent. In some countries, yields from rain-fed agriculture could be reduced by up to 50% by 2020.” (IPCC 2007a)
Water availability in drylands is expected to decrease in the next 40 years by 10-30% while drought-affected areas will likely increase in extent and floods are expected to be more frequent (IPCC 2007a). Overall this is expected to have severe impacts on food security in drylands especially in subsistence sectors (IPCC 2007a) and will be worsened by the expected warming of lakes and rivers with effects on fish productivity. In addition, climate change is projected to overall severely affect the health of especially vulnerable people through malnutrition, decrease in water quality, heat waves, floods, storms, fires and droughts (IPCC 2007a). Impacts of climate change are already felt in drylands. For instance in the Sahelian region crop productivity has dropped due to warmer and drier conditions and thus a shorter growing season (IPCC 2007a). Hence, drylands and the people living in drylands appear to be one of the most affected by climate change, given the already existing water stress, land degradation and the limited capacity to adapt in these regions (IPCC 2007a; MA 2005 a3).
Case study: Sudan
The drought-prone Bara province is situated in western Sudan and is mainly composed of desert scrub vegetation and ondulating sand dunes. The average rainfall is around 250 mm per year with significant seasonal and inter-annual rainfall variability. The land is becoming increasingly degraded as a result of recurring droughts, cultivation of marginal lands, overstocking of livestock and fuelwood gathering. Since 1992 community based rangeland rehabilitation (CBRR) for carbon sequestration measurements have been implemented in 17 villages in central Bara province. These measurements mainly consisted of the implementation of simple model community-based natural resource management to prevent overexploitation of marginal lands and rehabilitate rangelands and the diversification of local production systems to ensure sustainability of the approach as well as to improve socio-economic conditions.
The outcomes of the CBRR project were very successful. Over 700 ha of rangeland were improved. Other achievements of the project included: the establishment of local institutions to coordinate community natural resource management and community development activities, regeneration and stabilization of five km of sand dunes to halt expansion of the desert, construction of windbreaks to protect farms from soil erosion, restocking of livestock by replacing goat herds with more resilient and less damaging sheep, creation of water management sub-committees to better manage wells and the preparation of a drought contingency plan. The main lesson learned was that in order to secure the long-term effectiveness of the achievements of this project it is crucial to build the capacity of the affected communities in order to enable them to cope with climate-induced stresses (IISD, 2003).
Further Reading
Indigenous Peoples, Climate Change, and the United Nations
Indigenous Peoples and Climate Change: A Human Rights Issue
Deforestation and the Baka and Bambendzele Indigenous Peoples of Africa
The Raika Indigenous Peoples of Rajasthan and Drought
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